研究成果・発表論文

Discovery of a Hot Corino in the Bok Globule B335

Imai, Muneaki,   Sakai, Nami,   Oya, Yoko,   López-Sepulcre, Ana,   Watanabe, Yoshimasa,   Ceccarelli, Cecilia,   Lefloch, Bertrand,   Caux, Emmanuel,   Vastel, Charlotte,   Kahane, Claudine,   Sakai, Takeshi,   Hirota, Tomoya,   Aikawa, Yuri,   & Yamamoto, Satoshi


要旨
We report the first evidence of a hot corino in a Bok globule. This is based on ALMA observations in the 1.2 mm band toward the low- mass Class 0 protostar IRAS 19347+0727 in B335. Saturated complex organic molecules (COMs), CH$_3$CHO, HCOOCH$_3$, and NH$_2$CHO, are detected in a compact region within a few 10 au around the protostar. Additionally, CH$_3$OCH$_3$, C$_2$H$_5$OH, C$_2$H$_5$CN, and CH$_3$COCH$_3$ are tentatively detected. Carbon-chain related molecules, CCH and c-C$_3$H$_2$, are also found in this source, whose distributions are extended over a scale of a few 100 au. On the other hand, sulfur-bearing molecules CS, SO, and SO$_2$ have both compact and extended components. Fractional abundances of the COMs relative to H$_2$ are found to be comparable to those in known hot corino sources. Though the COMs lines are as broad as 5-8 km s$^-1$, they do not show obvious rotation motion in the present observation. Thus, the COMs mainly exist in a structure whose distribution is much smaller than the synthesized beam (0.″58 × 0.″52).




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